Method and means fob propelling graft navigating fluid mediums



L G. BOSTEDO. METHOD AND MEANS FOR PROPELLING cam NAVIGATING FLUIDmamums.

APPLICATION FILED AUG-3 197- I 1,305,340. PatentedJune 3, 1919.

. 2 SHEETS-SHEET I v r i m vww ,V/ I 1.

L. G. BOSTEDO. METHOD AND MEANS FOR PROPELLING CRAFT NAVIGATING FLUIDMEDIUMS.

APPLICATION FILED AUG-3. 1917.

Patented June 3, 1919.

2 SHEETS-SHEET 2.

r M m v UNITED STATES PATENT oFFIoE.

LOUIS G. BOSTEDO, DE LOS 'ANGELES, CALIFORNIA,

METHOD AND MEANS FOR PROPELLING CRAFT NAVIGATING FLUID MEDIUMS. Z

'1' all who) it may concern:

Be it known that 1. Lotus G. Bos'rnno, a

' citizen of the United States, residing at Los Angeles, in the countyof Los Angeles and State of California, have invented certain new anduseful Improvements in Methods/of and Means for Propclling Craft Nav gatng Fluid Mediums, of which the followmg 1s a specification.

This invention relates to an improved method of and means for propellingair and water craft; the broad principle of the 1nvention being capableof useful application to the propulsion of air craft and surface andsub-surface water craft.

In the present known devices for effecting the propulsion of both airand water craft, all the propeller blades can do is to bat the moleculesof the air or water and recelve the recoil from the molecules which theystrike. It is the impact of the recoiling moleculescollectively theirpressure-which pushes the craft forward. And a propeller blade is thecraft travels, without the intervention of' any motor, engine orpropeller blades or any other moving parts.

In its simplest and what might be termed its most rudimentary form, myinvention employs a tube that constitutes in effect a gas expansionchamber. This tube has a relatively small inlet for air or oxygen at itsfront or forward end and a relatively large outlet for the products ofcombustionor expansion at its rear end, and to this tube,

where the molecules are energized by the heat of combustion, are applieda means for introducing, a ct or spray of fuel preferably in liquid orvapor form to mix with the air or oxygen, and a means for initlallyigniting .the combustible charge. When adapted for the propulsion of aircraft, theratio of the diameters of the front and rear openings isSpecification of Letters Patent.

-front inlet are overcome by Patented June 3, 1919.

Application filed August 8, 1917. Serial No. 184,362.

such that, after allowing for the vaporization of the fuelsprayed intothe combustion chamber and the expansion of the products of combustionby the heat, the velocity of the outflowing gases is less than thevelocity of the tube through space. Because of this, the gases seekingto flow out through the the superior pressure of the atmospheric airwhich, considered relatively to the tube, same as in an ordinary housefurnace, except that in the present case the tube moves through theatmosphere, while the house enters it the furnace is stationary. Or, .inlieu of the latter, a continuous current of a1r or oxygen may be forcedinto the small end of the tube by means of a fan, positive blower, orair compressor, or by expansionof liquid air or oxygen by the heat ofthe atmosphere, or, when adapted for the propulsion of water craft, bythe heat of the body of water on or in which the craft travels. a

In the simple form above outlined, the efiiciency of such a device wouldnecessarily be somewhat limited for the reason that the volume of airwhich can pass through the largest tube that a craft could carry wouldover-cool the combustion chamber and thereby cause incompletecombustion. 'On the other hand, if enough fuel is burned to maintaingood combustion, the exhaust gases will carry off too much unused heat.

To overcome'the foregoing objections, I

have devised a form of combustion tube wherein the air is preliminarilyheated before entering the combustion chamber of the tube and minglingwith the fuel, and Wherein the products of combustion pass from thecombustion chamber directly into what I term an expansion chamberwherein they commingle with an additional volume of air entering throughthe front of the tube, expanding the latter, the exhaust passing in acontinuous stream out of the rear end of the expansion chamber. Thisexpansion chamher is preferably of considerable length so as to allowan, expansion of gases within the chamber down to at least thetemperature of the surrounding air.

In order to facilitate aclear understanding of the principle of myinvention, and to illustrate a practical embodiment thereof as appliedtothepropulsion of air craft, reference is made to the accompanyingdrawings .gramatic form an apparatus by W knowh to and undelstood bythose skilled in the art of. internal combustion motors and .the art offluid fuel burning.

Referring to the drawings,

Figure 1 is a longitudmal tion broken away between its ends through-theexpansion chamber and taken on the line 1-1 of Figs. 2 and 3 are crosssections on the lines 22 and 33 of Fig. 1 respectively. Fig. 4 is adetail view similar to the left hand end of Fig. 1 and illustrating theapplication of a ositive air feeding device for the combustion chamber.

Referring a tube that constitutes the expansion chamber, this tubehaving an end wall 6 at its forward end and being open at its rear end,and of such a, length as theory and expenment may determine to affordthe highest To and in advance of the forefliciency. ward end wall 6 aresecured four coaxial tubes 7, 8, 9 and 10. The tube 9 is closed at itsforward end by the wall 11 and the Walls thereof are lined with firebrick or similar highl refractable material as indicated. Pre erablythere is also applied to the outer side of the end wall 11 a protectingshield 12 of heat insulating material designed to permit the end wall 11of the furnace to remain hot and practically unaffected by the cold airstriking the same. The inner tube 10, which is open at its forward end,constitutes an air supply con-' duit and also a protective housing foran oil inlet tube 13 that terminates at its free end in a vaporizer oratomizer 14 designed to spray oil directly into the interior of the tube9 which constitutes the furnace chamber.- The oil pipe 13 connects withan oil reservoir 15 in which a suitable air pressure is .maintained froma com 'ressed air tank 16, the pressure being a mitted and controlled bya valve 17 in the pipe 18 1 connecting the compressed air tank with sothat the air enters the combustion chamber along with the vaporized oilthrough the open forward end of the inner tube 10.

In the end wall 6 of the expansion chamher are formed a series ofopenings 20' (Fig;

to the drawings, 5 designates 23 .with a series 0 2) that are disposedbetween and in alternating relation with the ducts 19, and through theseopenings the hot products of combustion pass from the combustion chamberinto the expansion chamber formed by the tube 5. c

,The end wall 6 of the tube 5 is further formed with a. series ofopenings 21 through which the larger body of cold air' entering betweenthe tubes 7 and 8 is permitted to flow into the expansion chamber.

Suitable dampers are employed to control the amount of air flowin to thecombustion and expansion cham ers respectively. In the drawings I-haveindicated a sleeve damper 21 surrounding the combustion chamber tube 9opposite the ducts 19 and formed with holes 22 which may be brought moreor less into register with the outer I ends of the ducts from theoperators .seat

.by suitable connections including a link (Fig. 3). Mounted on the innerface of the end wall 6 is a ring damper 24 rotatably mounted insupfporting lugs 25 and formed openings 26 adapted to be brought more orless into register with the holes 21, as shown in Fig. 2, said ringdamper being likewise controllablefrom the seat of the operator throughsuitable con nections including a link 27.

The combustion chamber is further equipped with means for initiallyigniting the dicated at 28 connected, of course, to a switch-controlledignition circuit and generator.

e1 such as an ordinary spar plug in- From the foregoing it will be seenthat distance to lnsure its being well heated. It

then turns inward through the ducts 19 into the central inlet tube 10,passing the atomizer and mixing with the atomized hot oil as it entersthe combustion chamber or furnace This arrangement provides formaintaining a white hot continuous fire in the furnace, whose thickrefractory walls do not lose more heat than is required to heat theincoming cold air taken by the inner air tube for the furnace. Asstated, the front end of the furnace is shielded by' the cap 12 fromthe'direct impact of the atmosphere.

The relatively large, expansion and mixing chamber 5 is made largeenough to give the cold air entering through the openings 21 time to mixwith the hot products of combustion'before the mixture discharges intothe atmosphere in the rear. 'To avoid unnecessary waste of heat thewalls of the expansion chamber 5 are likewise lined throughout thelrforward portion with heatinsulating material indicated at 29.

The several chambers and passageways are so proportloned as to attainthe highest eflican be unduly increased without unduly.

I diminishing the other, and experiment will best determine the properrelative proportions that will yield the highest efficiency.Furthermore, it is desirable to discharge the gases at a temperature asnearly as possible down to that of the atmosphere, this condition beingcontrolled by the insulation and the dimensions of the expansionchamber. It is theoretically possible to allow the discharging gases toacquire a velocity and momentum that will so rarefy them as to lowertheir temperature below that of the atmosphere; and in this case Ipropose to' pass them through a rear discharge section with muchconducting surface and of good conductin material like aluminum, thisbeing indicated at 5 in Fig. 1. This will permit the atmosphere tosupply enough heat to restore thetemperature of discharge to that of theatmosphere, thus maintaining the maximum velocity as well as efiiciency.

' tural conditions will admit.

Since the immediate cause of propulsion is the forward impact ofmolecules against the inside front ends of the furnace and expansionchamber, it follows that it is desirable to have the heat of combustionenergize the gases as near these surfaces as the struc- In the apparatusshown in Fig. 1 andthus far described .there has been assumed nopressure upon the inflowing cold air, other than that of the enteringdraft due to the forward motion of the craft. There are two practicalways by which increased air draft may be secured if found desirable. Inthe first case, the propulsive device shown and described maybe employedas an auxiliary propeller along with a standard mechanical propellersuch as is now used, and in this case the increased speed due to thepresence of the standard propeller will create a much stronger airdraft, which is equivalent to the mechanical draft of a fan inaccelerating the entrance of the air. The other way is to use forcedmechanical draft, such as a rotary fan or blower which I have indicatedat 30 in Fig. 4, the discharge of such blower being connected directlyto the front end of the tube 8 which supplies the air for combustion.With mechanically forced dra'ft, especially if it is of the positiveair-compressor type in which the air slip is negligible, the operationcan be under higher pressure and intensified. Higher dischargevelocities can be utilized,

and the combustion and expansion chambers may be smaller in proportionto thepower developed.

. I claim: v

1. A method of effecting propulsion of a craft or vehicle, whichconsists in contin uously burning fuel within a combination furnace andexpansion cha-In'ber open at its rear or trailing end and of such formand dimensions that the roducts of combustion expand laterally. as t eyflow from the furnace to the exhaust, lowering their temperature toapproximately that of the enveloping medium, t ereby applying the latentenergy of the fuel to maintaining the workin 'propulsive pressure ofthe. said products 0 combustion during their expansion, which pressurecontinuously urges the craft or vehicle and the exhaust products ofcombustionin opposite directions.

. 2. A method of effecting propulsion of a craft or vehicle, whichconsists in continuously burning fuel in a heat-insulated furnacecarried by the craft or vehicle, conducting the products of combustiondirectly from the furnace into an expansion chamber and therebyreducingtheir temperature'to approximatelythat of the enveloping medlumwhlle maintaining their pressure above that of the enveloping medium,and discharging said products directly from the expansion chamber intothe enveloping medium, whereby substantially all of the latent energy ofthe fuel is-applied' to maintain the working propulsive pressure of theyproducts of combustion at the maximum volume of discharge into theenveloping medium.

3. A method of efiecting propulsion of a craft or veh1cle, whic'hconsists in continuously burning fuel in a furnace carried by 1 whichthe expansionis limited to an extent at'which the temperature will bethe most favorable for perfect combustion, and, second, theexpansion-chamber stage in which the expansion is sufficient to lowerthe temperature and condition the velocity to the point of mostefficient reaction; thereby applying the fuel energy to maintaining theworking pressure of the products of combustion throughout theirexpansion.

4. A method of effecting propulsion of a craft orvehicle, which consistsin maintaining a continuous flow of fuel and a combustion supportinfluid into a furnace carried by the said craft or Vehicle, and acontinuous flow of the products of th'eir combustion from the furnaceintoand through an expansion chamber, and thence discharging into theenvelopin medium at a working pressure substantially constant, but withthe entrance pressure kept sufliciently above the exhaust pressure tomaintain the required supply of fuel and combustion-supporting fluid;the expansion of the fluids occurring in two stages, namely, first, inthe furnace by combustion to a temperature favorable to perfectcombustion at the conditioned working pressure, and, second, in theexpansion chamberto the volume which will bring the temperature toapproximately that of the enveloping medium at the conditioned dischargepressure; thereby converting the maximum portion of the fuel energy intothe increased molecular energy ofthe products of combustion -required tomaintain their working pressure throughout their expansion.

5. A method of effecting propulsion of a craft or vehicle, whichconsists in maintaining bycontinuous combustion in a combination furnaceand expansion chamber carried by said craft or vehicle the workingpropulsion pressure of a' continuous stream of fluids which are keptflowing through said furnace and expansion chamber, said fluidscomprising fuel and air or oxygen when they enter the furnace, and theproducts of their combustion plus additional air or oxygen when theyenter the expansion chamber; the relative dimensions of the entrance,exit, furnace and expansion chamb enbeing such that the expansion of thestream of fluid in the furnace is just sufficient to condition thetemperature of perfect combustion, and in. the expansion chamber thetemperature is lowered and the velocity conditioned to the point of mostefficient reaction; thus utilizing the utmost portion of the fuel energyin maintaining the maximum volume of the motive fluid at the workingpropulsion I pressure.

6. A propulsive device for craft navigating a fluid medium, consistingof a propulsion-tube rigidly attached to the craft and closed at itsforward end and open at its rear or trailing end, and means foreffecting by internal combustion a continuous and substantially uniformexpansion of an expansible fluid within said propulsion-tube.

7. A propulsive device for craft navigating a fluid medium, consistingof a propulsion-tube rigidly attached to the craft and open at'its rearor trailing end, means for continuously supplying a combustible fluid tosaid tube, and means for initially igniting said combustible fluid insaid tube.

8. A propulsive device for craft navigating a fluid medium, consistingof a propulsion-tube rigidly attached to the craft and open at its rear.or trailing end, means for continuously supplying fuel and acombustion-supporting agent to said tube, and

means for initially igniting the fuel in said tube. V

9. A propulsive device for craft navigating a fluid medium, consistingof a propulsion-tube rigidly attached to the craft and open at its rearor trailing end, means for continuously supplying acombustible fluid tosaid tube, and means for initially igniting said combustible fluid insaid tube, said tube being of sufficient size to permit the products ofcombustion to expand down to substantially the temperature of thesurrounding fluid medium before being disber to mingle with and beexpanded by the products of combustion from said combustion chamber.

11. A propulsive device for air craft, consisting of apropulsion-tuberigid with the craft and open at its rear or trailing end, the forwardportion of said tube constitutand constituting an expansion chambercommunicating with said combustion chamber, means for supplying acombustible fluid to said combustion chamber, means for initiallyigniting said combustible fluid, and means for admitting air to saidexpansion chamber to mingle with and be expanded by the products ofcombustion from said combustion chamber, said expansion chamber being ofsuflicient' size to permit the gases therein to expand down tosubstantially the temperature ofthe surrounding atmosphere before beingdischarged into the latter.

12. A propulsive device for air craft, consisting of a propulsion-tuberigid with the craft and closed at its forward end and open at its rearor trailing end, the forward portion of saidtube constituting acombustion chamber or furnace and the-rear portion being' of largerdiameter and constituting an expansion chamber communicating at its.

forward end with the rear end of said combustionv chamber, .a tubesurrounding said combustion chamber and forming with the latter anannular passage for the intake and preliminary heating of air to supportcombustion, an air conduit leading from said annular passage to theinterior of said combustion chamber through the rear end ing acombustion chamber or furnace and the rear portlon belng of largerdlameterv of the latter, means for supplyingfuel to thecombustion-chamber, means for lnitially igniting the fuel, and means foradmitting air to said expansion chamber to commingle with and-beexpanded by the products of combustion therein.

13. A propulsive device for air craft, consisting of a propulsion-tuberigid with the craft and closed at its forward end and open at its rearor trailing end, the forward portion of said tube constituting acombustion chamber or furnace and the rear portion being of largerdiameter and constituting an expansion chamber communicating at itsforward end with the rear end of said com-- bustion chamber, an airinlet tube extending inwardly of the combustion chamber from the rearend of the latter, a tube surrounding said combustion chamber andforming with the latter an annularpassage for the intake and preliminaryheatin of air to support combustion, an air conduit leading from saidannular passage to said air inlet tube, an outer tube surrounding thesecond named tube and forming therewith an annular passage incommunication with said expansion chamber and serving to admitatmospheric air to the latter, means for supplying fuel to thecombustion chamber, and means for initially igniting the fuel in thecombustion chamber.

14. A propulsive device for air craft, consisting of a propulsion-tuberigid with the craft and closed at its forward end and open at its rearor trailing end, the forward portion of said tube constituting acombustion chamber or furnace and the rear portion being of largerdiameter and constituting an expansion chamber communicating at itsforward end with the rear end of said combustion chamber, an air inlettube extending expansion chamber and serving to admit atmospheric air tothe latter, all of said tubes being arranged coaxially with each otherand with said combustion and expan sion chamber, means for supplyingfuel within said air inlet tube, means for'controlling the amounts ofair admitted to said combustion and expansion chambers, and means forinitially igniting the fuel in the combustion chamber.

LOUIS G. BOSTEDO.

